Intermittent zipper sewing machine and method



1966 J. L. ROCKERATH ETAL 3,

INTERMITTENT ZIPPER SEWING MACHINE AND METHOD Filed June 9, 1964 5 heets-Sheet 2 I3 52,9558; MO7I'ION POINT 6 0 SPRINGS 4 ml/eflfofs CLOTH 4 ZIPPER ENTRYL/0/7/7 L p k /f;

JR 1 22 John E. GOppe/f y K/ i Harp/d J SC/VECA 26 ZPPER k7 By the/r affomeys J. L. ROCKERATH ETAL 3,286,668 INTERMITTENT ZIPPER SEWING MACHINE AND METHOD Nov. 22, 1966 5 Sheets-Sheet 5 Filed June 9, 1964 John E. Gopperf Ham/J J Sch/e c/r 5y #2 air of/omeys United States Patent Ofifice 3,286,668 Patented Nov. 22, 1966 York Filed June 9, 1964, Ser. No. 373,662 8 Claims. (Cl. 112-265) This invention relates to an intermittent zipper sewing machine and a method of operating the same. It relates more particularly to such a machine adapted to set intermittent lengths of taped zippers into garments or other material. Intermittent zippers commonly are used in lengths of from three to six inches. Each such zipper section has the usual tab and slider to connect staggered sets of teeth,(scoops). At the beginning end of each section there is the usual stop bar.

The invention is an improvement upon US. Patent 3,016,028 of January 9, 1962, granted to Harold J. Schreck and John L. Rockerath, for Sewing Machine and Method. The present invention is easily used in connection with the disclosures of this patent, but can be adapted to other machines.

In a sewing machine, a presser foot ordinarily is used to help form the stitches. So long as material passing through the stitch point is relatively uniform, this construction is satisfactory, because some flexibility or degree of yield is usually designed into the presser foot system. The presser foot has heretofore been used to form the stitch. Sewing in of a zipper, on the'other hand, presents difiiculties not compensated for by the ordinary presser foot design. The bulk of the slider and tab cannot pass the usual presser 'foot, throat plate and feed dog combination. The Schreck and Rockerath Patent 3,016,028 solved this problem by eliminating the feed dogs, thus providing a channel or added dimension below the fabric for the zipper and its elements. It installed a non-loaded, floating presser foot. This added dimension was in the throat plate and below the cloth-mounted zipper. That is, by eliminating the feed dogs, and thus providing a channel and a floating presser foot the inventors provided variable vertical clearance for the zipper bulk.

With the machine and method of the cited Schreck and Rockerath patent it has been observed, occasionally, that friction on one side of the zipper fabric tends to produce a wavy effect in the fabric as finished. The presser foot apparently forces more fabric material than zipper into the stitch line. This wavy effect cannot occur with the present invention.

Prior to the instant invention, setting of intermittent zippers has been 'a slow process and often lacks uniformity when the work of one operator has been compared with that of another. Each operator has had to match exactly the length of slit in the garment which is to have a zipper to the length of the zipper to be installed. The cutting room staff has cut the basic slit in the garment but the sewing machine operator has had to fit the slit and the zipper material together. This step then has been followed by the operator cutting a Y-shaped notch in the bottom end of the slit so that the zipper could be sewn in properly at the bottom corners, near the stop bar. Each operator has had her own way both of fitting the slit to the zipper and of cutting the Y-shaped notch. This situation has resulted in non-uniform stretch or tension, at least as between operators. To be sure, in garments, the zipper and tapes are ordinarily relatively nonextensible. Nevertheless, in close fitting garments, nonuniform zipper installation is readily apparent.

It is an object of the present invention to provide improved automatic intermittent zipper setting sewing machine apparatus which substantially increases production rates.

It is another object of the present invention to provide improved automatic intermittent zipper setting sewing machine apparatus and a method for operating the same which overcome the various drawbacks heretofore experienced in the industry, as recited above.

Other objects will become apparent as the specification progresses.

The invention employs a drive mechanism to feed intermittent zipper sections through the sewing machine to the stitch point under controlled tension. There are fabric holding devices adjacent to the guide means to facilitate drawing the fabric taut and in line with the needles to obtain a clean, precise start of each zipper section by back-tacking same to the fabric at a point adjacent to the zipper stop bar. Means are provided to prevent flagging of the material being sewed.

With reference to the drawings generally:

FIGURE 1 is a view in front elevation of the invention showing a zipper being fed in between the throat plate and the guide plate. This view also shows the sewing needles and the spring guide flanges of the guide plate.

FIGURE 2 is a plan view of the attachment of the embodiment of the invention shown in FIG. 1 illustrating the stripper fingers, the position of the needles with reference 'to the guide plate, and the adjustable, fabric holding devices.

FIGURE 3 is a partly broken-away plan view of the adjustable center stop or split button around which the cloth is drawn.

FIGURE 4 is a plan view of one of the holding pins which holds the garment in place.

FIGURE 5 is a side view in elevation of one of the holding pins of FIG. 4 taken at right angles to FIG. 4 showing the slant position of the pin.

FIGURE 6 is a view in side elevation of the guide plate positioned in the sewing machine taken along the centerline of FIG. 2. This view also shows the cooperative relation of the holding pins, split button, and the needles.

FIGURE 7 is a plan view of the guide plate per se, of the invention, showing a few elements of the apparatus related thereto.

FIGURE 7a is a longitudinal sectional view of the guide plate illustrating the edge of one of the flanges, and also showing a stripper, a pin and locating the tape and fabric relative to these elements as they pass through the guide.

FIGURE 8 is a plan view showing material positioned by the holding pins in a straight line for back-tacking by the needles.

FIGURE 9 is a plan view showing the material being laid around the split button preparatory to a zipper being sewn in, for maintaining uniform row stitching along the zipper tapes.

The sewing machine, indicated generally in the drawings by the arrow 1, may be similar to that shown in the 3,016,028 Schreck and Rockerath patent. This is a machine essentially of ordinary construction, equipped with thread tension and feed mechanisms which are indicated generally by the arrow 16. A table is used to support the machine upon the usual bedplate, not shown.

There is a guide plate 4 mounted on a throat plate 7. The guide plate is basically a U-s'haped structure in plan with the open end at the front of the machine. There is a slotted stripper member 8 extending rearward from the closed end of the U. Two spring guide flanges 3 are fitted along the line of feed of tapes and zippers between the legs of the guide plate 4. These are integral with the plate at the closed end of the latter. The guide flanges 3 are adapted to move up and down with relation to the guide plate 4, the point about which motion occurs being at the point 30, the greatest motion of arc of the flanges 3 being at the front of the machine. (See FIG. 6.) Releasable lever 5 is used to move the flanges 3 downward. The lever 5 may be held in that position by wire 25 connecting the usual foot pedal apparatus. Feed dogs have been omitted from the throat plate 7, as taught by the Schreck and Rockerath 3,016,028 patent. The throat plate extends but .part Way along the feed line toward the needles, to form an enlarged passage 2 for sliders.

The guide plate 4 and throat plate 7 construction, together with the spring guide flanges 3 thus form sufficient passage space or trackway to admit and pass through a zipper and all its elements.

Flagging is prevented in the embodiment of the invention shown here, in the absence of a presser foot, by the stripper member 8, which member holds the zipper tapes in place. The slotted construction of the stripper 8 provides room for the needles. The feed and drive mechanism employed is similar to that disclosed by the Patent 3,016,028. There is a fixed, driving draw roller 9 in driving contact with an adjustable driven roller 10 mounted in yoke and shaft combination 11, supporting spiral spring 12 (see FIG. 6). This structure enables the roller 10 to yield or give somewhat to compensate for unevenness of goods being moved through the sewing machine, such as occurs, for example when a zipper slider passes through the draw roller mechanism 9, 10.

The invention is described in connect-ion with a two needle sewing machine. Each needle 13 sews along one side of the zipper tape 18. Just forward of the needle positions and midway between these positions, an adjustable center stop or split button 14 is mounted. Slightly to the rear of this position (toward the draw rollers as viewed from the input or front of the machine) two fabric holding pins or hooks 15 are adjustably mounted, one exteriorly of each needle. These hooks are disposed generally rearward, parallel to the line of feed. They are shown horizontal, as viewed from the side, but may be tilt-ed slightly upward. Both the center stop 14 and the pins 15 are mounted on the guide plate 4 at the closed end of same and at the point thereof where the stripper element 8 joins the plate 4.

Zipper tapes 18 and intermittent lengths of zippers 17 with sliders 19 and stop bars 20 spaced along said tapes are introduced into the guide plate 4 through the lever 5, and under the guide flanges 3 as shown at the point 22 in FIG. 6 by an arrow. The tapes are then fed between draw rollers 9 and 10. Lever 5 is then brought down. The exertion of force upon the spring guide flanges 3 caused by this step tensions the tapes between the draw rollers and the point of introduction of the tapes into the mechanism.

The step of feeding intermittent zipper sections, tape strips and to-be-sewed fabric through the sewing machine, is combined with the steps of guiding the zipper sections and tape strips under tension, through the machine; drawing the fabric taut and in-line with the machine needles over the fabric holding pins; cross-stitching the fabric and tape strips together at a point just below the zipper stop bar, to obtain a clean, secure corner start; removing the fabric from the pins; and drawing it around a center stop to guide the subsequent stitch formation. Refinement of tension control is obtained through appropriate apparatus disclosed in the Patent 3,016,028.

The elimination of the presser foot and installation of stripper fingers 8 overcomes the above-mentioned drawback of occasional pucker or wavy irregularities in the goods as produced. That is, frictional drag on the goods being sewed is eliminated, and the quantity of material and zipper presented to the needles is uniform. Therefore, once the tension has been set, as described above, the feed of zipper sections is automatic.

The steps of feeding and guiding under tension have brought zipper and tapes to the needles 13. Attention is now directed to the pins 15 and the center stop 14. While the zipper and tapes are fed into the machine from the front the fabric or material to be sewed can be brought up either from behind or from in front of the needles 13, as physical conditions may dictate. For the present discussion, the fabric to be sewed will be assumed to be a garment. Normally, the slit made in the garment for the zipper will have been made by the cutting room staff. The machine operator brings the thus prepared garment to the stitch point at the moment when a zipper stop bar has been drawn almost to the needle positions. As each Stop bar reaches this position it can be seen through the stop bar sighting slot 26. The fabric at the bottom of the garment slit is brought up, by the operators hands 21, under the holding pins 15 and against them so that the garment fabric describes a taut, straight line between the two pins, with the side edges of the slit being draped away from the pins at an angle, as in FIGURE 8. The operator then folds the fabric under, at the bottom end of the slit, and uses the machine, back-tacking it to the tapes at a point just below the zipper stop bar. The corners are thus established quickly, accurately and securely. The prior art method involved the previously described laborious and non-uniform individual notching of a Y at the bottom corners of the slit.

After back-tacking and thus starting the zipper into the garment at the bot-tom corners of the slit the operator draws the garment toward the rear, fitting the excess between the draw rollers 9 and 10 until the garment is taut between the draw rollers and the needles 13. The adjustable draw roller shown in the Patent 3,016,028, facilitates this operation. The side edges of the garment slit are then hand folded and drawn snug around the split button or center stop 14 and the operator sews the tapes to these edges down to the end of the garment. The center stop is used throughout the edge sewing as a guide to the maintenance of uniform width between the two rows of stitches. It also maintains edges folded.

Upon reaching the end of the garment, the operator sews off in the usual fashion, and stops the machine just long enough to cut the thread, lay aside the garment and pick up the next garment for setting; whereupon the above operations are repeated.

The step of doubling, or folding the fabric edges under just prior to stitching is performed by hand in the present invention. The-re is no folder device per se. On the other hand, once the edges of a slit have been folded, and the fabric drawn around the center stop, sewing progresses without the operator having to further fold the material.

It will be observed that the zipper sliders such as 1 9, readily pass through the guide plate 4 and beneath the center stop 14 due to the above described passage or trackway 2 which accommodates such bulk. At the same time, constant tension is maintained on the tapes 18 by the flanges 3 to ensure uniform tape and zipper feed, and ultimately, production of uniformly neat goods.

The reduced frictional drag on fabric disclosed by the invention suggests some possible uses for the apparatus not heretofore feasible. For instance, live rubber fabric passes through the device. This means that resilient, foul-weather garments, as well as fibrous garments, can have intermittent zippers set therein by the invention.

Production rates are substantially increased with adoption of the invention. Whereas, heretofore, one skilled operator might turn out nine dozen zipper settings in -a day, What with the fitting and notching required, that same operator, using the invention, can turn out about four times as many zipper settings in a day. Furthermore, tension in the zippers set by one operator will be uniform when com-pared with those set by a second operator. Zipper setting irregularities will be substantially fewer, as will goods rejected for such irregularities.

The ordinary presser foot has the function of preventing flagging, as has already been mentioned. A second, and mentioned, important function of the presser foot is to help form stitches. In the present invention, there being no presser foot, stitch forming is accomplished by the zipper tapes 18 per se, the spring guide flanges 3 and the stripper 8, combined.

The embodiment of the present invention above described is particularly well adapted for use with the disclosures of the Sch'reck and Rockera-th Patent 3,016,028 referred to at several points throughout the specification. The invention is not to be understood as being intended for use with only the disclosures of the said patent. Such adaptations or changes in the present invention as workers normally skilled in the art may evolve are to be understood as coming within the ambit of the preceding specificati-on and the claims that follow.

' We claim:

1. A machine for sewing separated lengths of zipper tape into fabric,

having drive mechanism to feed separated lengths of zipper tape through the machine,

guide means in the line of feed which provides a vertical dimension for free passage of zipper tape and zipper through the stitch point,

and fabric holding pins adjacent to the guide to facilitate aligning and drawing the fabric taut during backtacking.

2. A machine for sewing separated lengths of zipper tape into fabric, including tape guide means,

having drive mechanism to feed separated lengths of zipper tape through the machine,

a throat plate adapted to facilitate passage of zipper parts through the stitching point,

and fabric holding pins above the throat plate to facilitate aligning and drawing the fabric taut during backtacking.

3. A machine for sewing separated lengths of zipper tape into fabric,

having drive mechanism to feed separated lengths of zipper tape through the machine,

a throat plate adapted to facilitate passage of zipper parts through the stitching point,

a guide plate spaced above the throat plate to facilitate control of zipper parts and tape, spring guide plate flanges on the guide plate for bearing against zipper lengths passing under the said flanges,

and fabric holding pins on the guide plate, disposed externally of the stitching point and extending directly rearward therefrom to facilitate aligning and drawing the fabric taut during back-tacking.

4. A machine for sewing separated lengths of zipper tape into fabric, having drive mechanism to feed separated lengths of zipper tape through the machine,

a throat plate adapted to facilitate passage of zipper parts through the stitching point,

a guide plate spaced above the throat plate to facilitate control of zipper parts and tape,

spring guide plate flanges on the guide plate for bearing against zipper lengths passing under the said flanges,

a stripper member mounted above the throat plate at the point of stitching, and rearward,

and fabric holding pins on the guide plate, disposed externally of the stitching point and extending directly rearward therefrom to facilitate aligning and drawing the fabric t-aut during back-tacking.

5. A two-needle machine for sewing intermittent zippers into fabric,

comprising drive mechanism to feed fabric to be sewed and separate zipper tape sections, including sliders, through the sewing machine, in combination with means to guide zipper tape sections under controlled tension to the stitching points,

comprising spring guide flanges for controlled but ready passage of zipper tape sections and sliders between said flanges, which flanges define space equal to the width of the zipper tape sections along the line of feed thereof, there being unlimited vertical clearance for the sliders along the middle of the width of each zipper tape section,

a throat plate underlying the guide flanges, extending only part way along the line of feed, to facilitate the passage of zipper sliders,

a lever attached to the guide flanges for releasably holding the flanges in tension-exerting position on zipper tape sections passing under the guide flanges,

fabric-holding devices adjacent to the guide means comprising pins disposed to hold fabric taut and in a line which is straight with reference to the needles for back-tacking the fabric and each zipper tape section thereto,

and a center stop adjacent to the needles and pins around which stop fabric is adapted to be laid after back-tacking, for maintaining uniform row stitching.

' 6. A two needle zipper setting sewing machine comprising rear-mounted adjustable draw roller apparatus for feeding to-be-sewed fabric and intermittent zipper tape sections and sliders through the sewing machine,

in combination with a, guide plate disposed front to rear of the machine along the line of feed for zipper tape sections and sliders,

spring guide flanges on the guide plate for controlled but ready passage of zipper tape sections and sliders between said flanges, which flanges define free space equal to the width of the zipper tape sections all along the feed line, there also being unlimited vertical clearance for the sliders all along the middle of the width of the zipper tape sections,

a lever attached to the spring guide flanges for releasably holding the flanges in tension-exerting position on the zipper tape sections passing thereunder,

a throat plate underlying the spring guide flanges and extending only part way along the line of feed, to provide a trackway for sliders, in cooperation with the spring guide flanges,

adjustable, rear-pointing fabric-holding pins disposed on top of the guide plate and just exterior of each needle to hold fabric taut and in a line which is straight and parallel with reference to a line drawn between the needles for back-tacking the fabric with each zipper tape section to form neat, secure corners,

an adjustable split button on top of the guide plate adjacent the needles, around which button fabric is adapted to be laid after the back-tacking, for maintaining uniform rows of stitching,

and a slotted stripper member attached to the guide plate adjacent to the needles, to prevent flagging, and to facilitate proper location and formation of stitches;

whereby intermittent zippers can be quickly set with accuracy and uniformity without pre-set garment notching.

7. A method of setting and sewing separated lengths of zipper tape into fabric comprising the step of feeding separated zippers, tape strips and to-be-sewed fabric through a sewing machine,

in combination with the steps of guiding the zippers and tape strips under tension, through the machine,

drawing the fabric taut and in line with the machine needles over fabric-holding pins,

back-tacking the fabric and tape strips together while the fabric is aligned with the pins, to obtain clean finished corners at the beginning of each separate zipper,

and stitching the fabric and tape strips together along the length of the tapes to the end of each separate zipper.

8. A method of setting and sewing intermittent zippers into fabric comprising the step of introducing tape strips and intermittent zipper sections spaced therealong into a guide and under spring guide flanges thereof,

in combination with the steps of passing the tape strips and intermittent zipper sections clear through the guide and through adjustable roller mechanisms, forcing the spring guide flanges to bear against the tape strips, thus tensioning the tape strips and intermittent zipper sections, drawing the tape strips and intermittent zipper sections along through the line of feed by means of the adjustable roller mechanisms to the point where a zipper stop bar appears just forward of the stitch point, introducing fabric to-be-sewed, already slitted, to the stitch point, and folding the bottom edge of the slit,

drawing the fabric taut over holding pins, back-tacking the fabric and the zipper-bearing tape strips together, just behind the zipper stop bar, while the pins engage the fabric, to start the zipper set with clean, secure corners, folding the side edges of the fabric slit, disengaging the fabric from the pins, and drawing the fabric around the center stop adjacent the holding pins and stitching the tapes .8 and fabric together along the length of the zipper to set the same, by using the center stop to maintain edges folded and rows of stitching uniform.

References Cited by the Examiner UNITED STATES PATENTS 15 JORDAN FRANKLIN, Primary Examiner.

I. R. BOLER, Assistant Examiner. 

1. A MACHINE FOR SEWING SEPARATED LENGTHS OF ZIPPER TAPE INTO FABRIC, HAVING DRIVE MECHANISM TO FEED SEPARATED LENGTHS OF ZIPPER TAPE THROUGH THE MACHINE, GUIDE MEANS IN THE LINE OF FEED WHICH PROVIDES A VERTICAL DIMENSION FOR FREE PASSAGE OF ZIPPER TAPE AND ZIPPER THROUGH THE STITCH POINT, AND FABRIC HOLDING PINS ADJACENT TO THE GUIDE TO FACILITATE ALIGNING AND DRAWING THE FABRIC TAUT DURING BACKTACKING. 